LED die structures have made in roads into a variety of illumination devices over the past decade, in particular as the main illumination device of a photography strobe (camera flash). The use of LED die structures allows fine-grained electronic control of the intensity of the illumination as well as its color. As an example, a camera flash may contain multiple LED chips, where one is designed to produce a cool white output, while the other is designed to produce a warm white output. The cool white chip includes an LED die structure covered with a yellow phosphor, while the warm white chip has another LED die structure that is covered with yellow and red phosphors. When stimulated by a primary light from the LED die, the phosphor emits secondary, wavelength-converted light at a longer wavelength, such that the combination of the secondary wavelength-converted light and the primary light emitted from the two LED dies structures (typically blue LEDs that are within +/−10 nm, for example) result in a combined, white illumination. In one case, the cool white portion of the flash may be designed to produce a correlated color temperature (CCT) of 5500K. The warm white chip produces a warmer light, at a target CCT of 2800K. Each of the LED die structures is driven with a regulated current independently of the other, so as to control the intensity of the combined white illumination as well as the shade of the white illumination. In other words, the combined white illumination may be varied between 2800K (warm) and 5500K (cool), by varying the ratio of the regulated currents that are applied to the two LED die structures. For example, to obtain 5000K (a cool white light), more current is injected into the cool white chip than into the warm light LED chip.